Clare Bradley, Jan Mitchell, Alison Woodcock, James Wolffsohn, Stephen J Anderson, Timothy Ffytche, Martin Rubinstein and Winfried Amoaku (2008) The MacDQoL individualized measure of the impact of macular degeneration on quality of life: reliability and responsiveness. American Journal of Ophthalmology, 146 (3). pp. 447-454. ISSN 0002-9394
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PURPOSE: To investigate the MacDQoL test-retest reliability and sensitivity to change in vision over a period of one year in a sample of patients with age-related macular degeneration (AMD). DESIGN: A prospective, observational study. METHOD: Patients with AMD from an ophthalmologist's list (n = 135) completed the MacDQoL questionnaire by telephone interview and underwent a vision assessment on two occasions, one year apart. RESULTS: Among participants whose vision was stable over one year (n = 87), MacDQoL scores at baseline and follow-up were highly correlated (r = 0.95; P < .0001). Twelve of the 22 scale items had intraclass correlations of >.80; only two were correlated <.7. There was no difference between baseline and follow-up scores (P = .85), indicating excellent test-retest reliability. Poorer quality of life (QoL) at follow-up, measured by the MacDQoL present QoL overview item, was associated with deterioration in both the better eye and binocular distance visual acuity [VA] (r = 0.29; P = .001, r = 0.21; P = .016, respectively; n = 135). There was a positive correlation between deterioration in the MacDQoL average weighted impact score and deterioration in both binocular near VA and reading speed (r = 0.20; P = .019, r = 0.18; P = .041, respectively; n = 135). CONCLUSION: The MacDQoL has excellent test-retest reliability. Its sensitivity to change in vision status was demonstrated in correlational analyses. The measure indicates that the negative impact of AMD on QoL increases with increasing severity of visual impairment.
This is a Draft version This version's date is: 09/2008 This item is peer reviewed
https://repository.royalholloway.ac.uk/items/4976fded-0c47-853a-4888-ad1aeb070113/1/
Deposited by () on 26-Mar-2010 in Royal Holloway Research Online.Last modified on 19-May-2011
(C) 2008 Elsevier whose permission to mount this version for private study and research is acknowledged. The repository version is the author's final draft.
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